Hi Jon,
installonlyn is part of SL 4.5, it is called yum-installonlyn, so you 
only have to do
   yum install yum-installonlyn
and it will be installed and turned on.  The default n is 2.

installonlyn was taken out of the generic yum-utils that comes from yum. 
  (nothing to do with the upstream vendor)  Since I didn't know why it 
was taken out, I left it out.

If you can find out why it was taken out of yum-utils, please let me know.

Troy

Jon Peatfield wrote:
> I originally asked this as part of another message in May, but maybe 
> no-one read past my driveling to this part -- well no-one replied 
> anyway... :-)
> 
> --start-quote--
> BTW is the installonlyn yum plugin available (as part of some package 
> somewhere)?
> 
>   http://people.redhat.com/~katzj/installonlyn.py
> 
>   #   A plugin for yum which only leaves n 'kernel' packages installed 
> instead
>   #   of infinitely doing installonly
> 
> I found a thread on a Centos mailing list suggesting it was part of 
> yum-utils but that was for Centos-4 anyway.
> 
>   http://lists.centos.org/pipermail/centos-devel/2006-August/002361.html
> 
> FC 5 and 6 appear to have this functionality included in the base yum 
> package and so does the yum in TUV-el5 if you see what I mean.
> 
> $ rpm -qlp yum-3.0.1-5.el5.src.rpm | grep installonlyn
> installonlyn.py
> 
> I don't know if it is *enabled* by default in those releases though!
> --end-quote--
> 
> Anyway after that I noticed that SL45 (at least) has yum-installonlyn 
> mentioned in the releasenotes -- built as part of yum-utils I think.
> 
> I think I understand how it got dropped (not part of SL's yum, but is in 
> TUV's yum, so missing from their yum-utils), though I may have missed 
> something more subtle.
> 
> Anyway to cut a long story slightly shorter I gave in and made the 
> trivial rpm for it and it does seem to work...
> 
> $ yum update
> ...
> Loading "installonlyn" plugin
> ...
> ============================================================================= 
> 
>  Package                 Arch       Version          Repository Size
> ============================================================================= 
> 
> Installing:
>  kernel                  i686       2.6.18-8.1.8.el5  sl-testedbits      
> 12 M
>  kernel-devel            i686       2.6.18-8.1.8.el5  sl-testedbits     
> 4.5 M
> Updating:
>  kernel-headers          i386       2.6.18-8.1.8.el5  sl-testedbits     
> 726 k
>  xorg-x11-xfs            i386       1:1.0.2-4        sl-testedbits      
> 68 k
>  xorg-x11-xfs-utils      i386       1:1.0.2-4        sl-testedbits      
> 27 k
> Removing:
>  kernel                  i686       2.6.18-8.1.4.el5  installed          
> 34 M
>  kernel                  i686       2.6.18-8.1.3.el5  installed          
> 34 M
>  kernel-devel            i686       2.6.18-8.1.4.el5  installed          
> 14 M
>  kernel-devel            i686       2.6.18-8.1.3.el5  installed          
> 14 M
> ...
> 
> without something like this my /boot would be full after another 10-15 
> kernel updates...
> 
> $ rpm -qil yum-installonlyn
> Name        : yum-installonlyn             Relocations: (not relocatable)
> Version     : 0.92                              Vendor: (none)
> Release     : 1.sl5x                        Build Date: Thu Jul 19 
> 00:30:49 2007
> Install Date: Thu Jul 19 00:33:01 2007      Build Host: 
> deluxe.damtp.cam.ac.uk
> Group       : Development/Tools             Source RPM: 
> yum-installonlyn-0.92-1.sl5x.src.rpm
> Size        : 7591                             License: GPL
> Signature   : DSA/SHA1, Thu Jul 19 00:32:10 2007, Key ID 04a6250b6173bb82
> URL         : http://people.redhat.com/~katzj/installonlyn.py
> Summary     : Yum plugin to only keep n 'kernel' packages
> Description :
> A plugin for yum which only leaves n 'kernel' packages installed
> instead of infinitely doing installonly
> /etc/yum/pluginconf.d
> /etc/yum/pluginconf.d/installonlyn.conf
> /usr/lib/yum-plugins
> /usr/lib/yum-plugins/installonlyn.py
> /usr/lib/yum-plugins/installonlyn.pyc
> /usr/lib/yum-plugins/installonlyn.pyo
> 
> Maybe it will be of use to some others...
> 


-- 
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Troy Dawson  [log in to unmask]  (630)840-6468
Fermilab  ComputingDivision/LCSI/CSI DSS Group
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